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CastCheck methodology v0.2 · data through 2026-08-30

Las Vegas Harry Reid · ECMWF AIFS Single · lead day 3

KLAS · aifs_single · lead 3

Target day = initialization date + 3 days. This page is a permanent link: the numbers change as history accumulates, the address and the methodology version do not.

Scores use the latest model version segment, aifs-single-gpid5, starting 2026-08-01 — days before that ran a different version of the model and are excluded rather than silently pooled. Of the scored days, 2 carry a QC flag on the observation.

JSON for this page CSV of the daily errors Cite this page

Every number for this combination

All four windows × both initializations × both interpolations × both variables. Errors are computed in °C and shown in °F; CI is a 95 % moving-block bootstrap interval. MAE debiased and skill, debiased remove the constant offset of the window first, so a station that the model always reads a degree too warm is not scored as if it had no skill — compare the two skill columns to see how much of the error is a fixed offset. n QC next to n counts days whose observation carries a QC flag.

VariableInitMethod Windown MAE °F MAE debiased Bias °F RMSE °F ±1 °F±2 °F±3 °F Skill Skill, debiased Period
tmax00Zbilinear30d27 2 QC5.07 [4.26, 5.70]1.86-5.02 [-5.70, -4.13]5.55 [4.76, 6.16]4% [0%, 11%]11%22%+0.04+0.642026-08-04 → 2026-08-30
tmax00Zbilinear90d27 2 QC5.07 [4.21, 5.72]1.86-5.02 [-5.72, -4.10]5.55 [4.64, 6.21]4% [0%, 11%]11%22%+0.04+0.642026-08-04 → 2026-08-30
tmax00Zbilinear365d27 2 QC5.07 [4.17, 5.76]1.86-5.02 [-5.76, -4.03]5.55 [4.61, 6.18]4% [0%, 11%]11%22%+0.04+0.642026-08-04 → 2026-08-30
tmax00Zbilinearall27 2 QC5.07 [4.12, 5.85]1.86-5.02 [-5.85, -4.03]5.55 [4.46, 6.26]4% [0%, 11%]11%22%+0.04+0.642026-08-04 → 2026-08-30
tmax00Znearest30d27 2 QC6.04 [5.15, 6.73]1.83-6.04 [-6.73, -5.15]6.47 [5.66, 7.09]4% [0%, 11%]7%11%-0.14+0.652026-08-04 → 2026-08-30
tmax00Znearest90d27 2 QC6.04 [5.10, 6.73]1.83-6.04 [-6.73, -5.10]6.47 [5.55, 7.15]4% [0%, 11%]7%11%-0.14+0.652026-08-04 → 2026-08-30
tmax00Znearest365d27 2 QC6.04 [4.99, 6.75]1.83-6.04 [-6.75, -4.99]6.47 [5.52, 7.10]4% [0%, 11%]7%11%-0.14+0.652026-08-04 → 2026-08-30
tmax00Znearestall27 2 QC6.04 [4.97, 6.81]1.83-6.04 [-6.81, -4.97]6.47 [5.48, 7.17]4% [0%, 11%]7%11%-0.14+0.652026-08-04 → 2026-08-30
tmax12Zbilinear30d27 2 QC4.93 [4.26, 5.55]1.92-4.93 [-5.55, -4.26]5.52 [4.53, 6.41]7% [0%, 17%]7%15%+0.07+0.632026-08-04 → 2026-08-30
tmax12Zbilinear90d27 2 QC4.93 [4.23, 5.60]1.92-4.93 [-5.60, -4.23]5.52 [4.44, 6.48]7% [0%, 17%]7%15%+0.07+0.632026-08-04 → 2026-08-30
tmax12Zbilinear365d27 2 QC4.93 [4.22, 5.69]1.92-4.93 [-5.69, -4.22]5.52 [4.34, 6.59]7% [0%, 18%]7%15%+0.07+0.632026-08-04 → 2026-08-30
tmax12Zbilinearall27 2 QC4.93 [4.19, 5.75]1.92-4.93 [-5.75, -4.19]5.52 [4.34, 6.57]7% [0%, 17%]7%15%+0.07+0.632026-08-04 → 2026-08-30
tmax12Znearest30d27 2 QC5.97 [5.34, 6.58]1.88-5.97 [-6.58, -5.34]6.45 [5.57, 7.27]0% [0%, 0%]7%7%-0.13+0.642026-08-04 → 2026-08-30
tmax12Znearest90d27 2 QC5.97 [5.31, 6.65]1.88-5.97 [-6.65, -5.31]6.45 [5.48, 7.33]0% [0%, 0%]7%7%-0.13+0.642026-08-04 → 2026-08-30
tmax12Znearest365d27 2 QC5.97 [5.31, 6.71]1.88-5.97 [-6.71, -5.31]6.45 [5.47, 7.48]0% [0%, 0%]7%7%-0.13+0.642026-08-04 → 2026-08-30
tmax12Znearestall27 2 QC5.97 [5.29, 6.79]1.88-5.97 [-6.79, -5.29]6.45 [5.44, 7.44]0% [0%, 0%]7%7%-0.13+0.642026-08-04 → 2026-08-30
tmin00Zbilinear30d27 2 QC5.11 [3.53, 6.43]2.05-4.94 [-6.43, -3.05]5.66 [4.36, 6.61]15% [0%, 37%]15%19%-0.07+0.572026-08-04 → 2026-08-30
tmin00Zbilinear90d27 2 QC5.11 [3.56, 6.51]2.05-4.94 [-6.51, -3.07]5.66 [4.40, 6.70]15% [0%, 36%]15%19%-0.07+0.572026-08-04 → 2026-08-30
tmin00Zbilinear365d27 2 QC5.11 [3.31, 6.52]2.05-4.94 [-6.52, -2.79]5.66 [4.18, 6.73]15% [0%, 40%]15%19%-0.07+0.572026-08-04 → 2026-08-30
tmin00Zbilinearall27 2 QC5.11 [3.41, 6.56]2.05-4.94 [-6.56, -3.02]5.66 [4.30, 6.73]15% [0%, 38%]15%19%-0.07+0.572026-08-04 → 2026-08-30
tmin00Znearest30d27 2 QC5.89 [4.16, 7.32]2.08-5.79 [-7.32, -3.82]6.43 [4.97, 7.48]4% [0%, 11%]19%19%-0.23+0.572026-08-04 → 2026-08-30
tmin00Znearest90d27 2 QC5.89 [4.19, 7.42]2.08-5.79 [-7.42, -3.89]6.43 [5.05, 7.60]4% [0%, 11%]19%19%-0.23+0.572026-08-04 → 2026-08-30
tmin00Znearest365d27 2 QC5.89 [4.01, 7.41]2.08-5.79 [-7.41, -3.70]6.43 [4.85, 7.57]4% [0%, 11%]19%19%-0.23+0.572026-08-04 → 2026-08-30
tmin00Znearestall27 2 QC5.89 [4.05, 7.52]2.08-5.79 [-7.52, -3.81]6.43 [4.98, 7.67]4% [0%, 11%]19%19%-0.23+0.572026-08-04 → 2026-08-30
tmin12Zbilinear30d27 2 QC5.05 [3.48, 6.34]2.08-4.86 [-6.34, -2.99]5.61 [4.36, 6.53]11% [0%, 27%]15%19%-0.06+0.572026-08-04 → 2026-08-30
tmin12Zbilinear90d27 2 QC5.05 [3.48, 6.41]2.08-4.86 [-6.41, -3.01]5.61 [4.35, 6.60]11% [0%, 27%]15%19%-0.06+0.572026-08-04 → 2026-08-30
tmin12Zbilinear365d27 2 QC5.05 [3.29, 6.43]2.08-4.86 [-6.43, -2.74]5.61 [4.17, 6.63]11% [0%, 29%]15%19%-0.06+0.572026-08-04 → 2026-08-30
tmin12Zbilinearall27 2 QC5.05 [3.39, 6.50]2.08-4.86 [-6.50, -2.93]5.61 [4.28, 6.70]11% [0%, 29%]15%19%-0.06+0.572026-08-04 → 2026-08-30
tmin12Znearest30d27 2 QC5.83 [4.03, 7.29]2.15-5.72 [-7.29, -3.73]6.40 [4.93, 7.48]7% [0%, 19%]15%19%-0.22+0.552026-08-04 → 2026-08-30
tmin12Znearest90d27 2 QC5.83 [4.12, 7.38]2.15-5.72 [-7.38, -3.81]6.40 [4.99, 7.56]7% [0%, 19%]15%19%-0.22+0.552026-08-04 → 2026-08-30
tmin12Znearest365d27 2 QC5.83 [3.92, 7.38]2.15-5.72 [-7.38, -3.59]6.40 [4.84, 7.56]7% [0%, 20%]15%19%-0.22+0.552026-08-04 → 2026-08-30
tmin12Znearestall27 2 QC5.83 [4.01, 7.51]2.15-5.72 [-7.51, -3.77]6.40 [4.95, 7.69]7% [0%, 19%]15%19%-0.22+0.552026-08-04 → 2026-08-30

+ model too warm · − model too cold · bias interval includes zero · ★ lowest MAE · = not distinguishable from the leader · ▼ significantly worse · n < 30 greyed and unranked · CI is a 95 % moving-block bootstrap interval.

Daily error, last 90 days

Daily forecast minus observed error in °F for ECMWF AIFS Single at KLAS, lead day 3, 00Z bilinear tmax+10+50-5-102026-08-04: -2.96 °F2026-08-05: -5.29 °F2026-08-06: -2.02 °F2026-08-07: -4.33 °F2026-08-08: -8.48 °F2026-08-09: -8.5 °F2026-08-10: -1.76 °F2026-08-11: -7.32 °F2026-08-12: -9.49 °F2026-08-13: -1.4 °F2026-08-14: -4.89 °F2026-08-15: +0.7 °F2026-08-16: -4.26 °F2026-08-17: -4.51 °F2026-08-18: -4.52 °F2026-08-19: -4.66 °F2026-08-20: -5.55 °F2026-08-21: -7.37 °F2026-08-22: -5.69 °F2026-08-23: -8.25 °F2026-08-24: -6.14 °F2026-08-25: -3.76 °F2026-08-26: -4.19 °F2026-08-27: -5.55 °F2026-08-28: -6.74 °F2026-08-29: -5.96 °F2026-08-30: -2.56 °F2026-08-042026-08-30°F, forecast − observed
Forecast − observed, °F, 00Z bilinear daily maximum. The dashed line is zero; the thick line is a centred 7-day mean, drawn only where the whole window is present. Gaps are days with no score, never interpolation. Hover a point for its date and value.
The same series as a table (27 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-2.56
2026-08-29-5.96
2026-08-28-6.74
2026-08-27-5.55
2026-08-26-4.19
2026-08-25-3.76
2026-08-24-6.14
2026-08-23-8.25
2026-08-22-5.69
2026-08-21-7.37
2026-08-20-5.55
2026-08-19-4.66
2026-08-18-4.52
2026-08-17-4.51
2026-08-16-4.26
2026-08-15+0.70
2026-08-14-4.89
2026-08-13-1.40
2026-08-12-9.49
2026-08-11-7.32
2026-08-10-1.76
2026-08-09-8.50
2026-08-08-8.48
2026-08-07-4.33
2026-08-06-2.02
2026-08-05-5.29
2026-08-04-2.96

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KLAS, lead day 3-10 to -9 °F: 1 day-9 to -8 °F: 3 days-8 to -7 °F: 2 days-7 to -6 °F: 2 days-6 to -5 °F: 5 days-5 to -4 °F: 7 days-4 to -3 °F: 1 day-3 to -2 °F: 3 days-2 to -1 °F: 2 days-1 to 0 °F: 0 days0 to 1 °F: 1 day1 to 2 °F: 0 days2 to 3 °F: 0 days3 to 4 °F: 0 days4 to 5 °F: 0 days5 to 6 °F: 0 days6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 4.89 · P90 |e| 8.35 °F-100+10 °Fn = 27 days
All scored days for 00Z bilinear daily maximum, 20 equal bins. The dashed marks are the 50th and 90th percentiles of the absolute error, mirrored on both sides. Hover a bar for its bin and count.
Bin counts as a table
From °FTo °FDays
-10.00-9.001
-9.00-8.003
-8.00-7.002
-7.00-6.002
-6.00-5.005
-5.00-4.007
-4.00-3.001
-3.00-2.003
-2.00-1.002
-1.00+0.000
+0.00+1.001
+1.00+2.000
+2.00+3.000
+3.00+4.000
+4.00+5.000
+5.00+6.000
+6.00+7.000
+7.00+8.000
+8.00+9.000
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08275.07 -5.02

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-04 → 2026-08-30 27
ECMWF AIFS Single2026-08-04 → 2026-08-30 27
ECMWF AIFS Single2026-08-04 → 2026-08-30 27
ECMWF AIFS Single2026-08-04 → 2026-08-30 27

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means ECMWF AIFS Single has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
NCEP GFS 27 +0.38 [-1.04, 2.04] no
GraphCast (IFS init) 25 -0.80 [-1.49, -0.09] yes
ECMWF IFS HRES 22 +1.46 [0.34, 2.37] yes
Persistence (baseline) 27 -0.23 [-4.30, 3.26] no

Cite this page

ShortCastCheck, KLAS aifs_single lead 3, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KLAS/model/aifs_single/lead/3/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KLAS (Las Vegas Harry Reid), model aifs_single, lead day 3. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KLAS/model/aifs_single/lead/3/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

JSON CSV all scores methodology v0.2 licence